Oil centrifuge with plural concentric separating zones



Oct. 5, 1948. B. C. RUNDQUIST OIL CENTRIFUGE WITH PLURAL CONCENTRICSEPARATING ZONES 3 Sheets-Sheet 2 Filed Feb. 12, 1943 Patented Oct. 5,1948 UNITED STATES PATENT OFFICE OIL CENTRIFUGE WITH PLURAL CONCEN TRICSEPARATING ZONES Bennett C. Rundquist, Cleveland, Ohio, assignor' to TheNational Acme Company, Cleveland; Ohio, a corporation of OhioApplication February 12, 1943, Serial No. 475,639

20 Claims. (Cl. 233-31) As is well known, lubricating oil picks up dustand metal particles, and forms carbon and sludge during its circulationin the motor so that its repeated use is veryinjurious to expensivebear.- ingssuch as those used in high speed motors of aeroplanes, tanks,etc., and for the purpose of cleaning this oil it has heretofore beenthe practice to use filters but these filters quickly become clogged andhave to be, cleaned frequently.

Therefore, for the. purpose of cleaning the oil'.

and separating therefrom all foreign matter, this improved centrifuge isprovided, it being so constructed that it can be readily connected orattached to the motor so that the oil, after it once passes through themotor, then. passes through the centrifuge before it passes back intothe motor. Consequently, any deleterious particles are removed and theefficiency of the motor increased and the life thereof prolonged.

The use of. centrifuges as usually constructed would not be possible inview of the limited space available in an aeroplane or tank and,therefore, it is the object. of this invention to provide a centrifugethat can be used in a practical way with aeroplanes and other motors inthe limited space available for that purpose.

Furthermore, as the oil in the motor is usually pumped into thepipelines under a pressure of 25 to. 4.0 pounds, it follows that whenthis oil leaves the lines after its passage through the motor and entersthe centrifuge for cleaning, this oil pressure. isnaturally reducedsince it passes through, the. centrifuge at a gravity feed and it isessential, therefore, that when the oil passes back to the motor fromthe centrifuge, it pass thereinto under pressure.

Therefore, one of the objects of the present improvement is theprovision of a centrifuge in which oil that passes from the motor to thecentrifuge and from the centrifuge back to the motor will be transmittedto that motor under substant ally the same pressure'under which it wasused while'in the, motor.

The present improvement therefore'has' to do with'rtheprovision of asimple, compact and effident-centrifuge particularly adapted. for clean-2 ingthe oil used in the motor during its circulation cycle.

In the drawings accompanying and forming a part'of this specification, II

Fig. 1 is a vertical sectional view ofthis improved centrifuge. i Fig. 2is a vertical sectional view of the lower half of the centrifuge showingone means for" pumping theoil back to the motor under pressure. Fig. 3is a horizontal sectional view taken on line 3-3 of Fig. 2.

Fig. 4 is a. vertical sectional view of the-lower half. of thecentrifuge illustrating a somewhat different arrangement for the pumpingof the oil back to the motor, and

' Fig. 5 is a bottom view of the centrifuge;

Similar reference characters indicate correspondingparts' in the severalviews. I

Before explaining in detail the present improvement and its mode ofoperation, I desire it understood that the invention is not limited tothe details of construction and arrangement of parts illustrated in theaccompanying drawings since the invention is capable of otherembodiments, and that the. phraseology employed is" for the purpose ofdescription and not. offlimita- I tion;

This improved centrifuge comprises a suitable supporting base or basehousing 2, a casing 3' and its cover 4'.

In the casing 3 is'located a rotatable bowl 5 d bearings and for thispurpose the bowl has its.

top and bottom provided with tapered spindles I and 8, each having a setof these ball bearings,

one set 9. at. thetopf andthe other set ID. at the.

bottom., p

The drive to the bowl fromthe motor shaft I l is obtained by a taperedslip bushing ll' fitting,

a tapered seat l2 in thetapered spindlefl'l, a. spring It being providedbetween the tapered bushing and the motor drive H to care for the:friction between the parts.

As thisdrive from the motor to the bowl is through a tapered fitting orjoint between the I motor shaft and the bowl, the spring operates notonly to keep these parts in. contact but also acts as a safety for, withthe bowl andv motor'runfning. at extremely highspeedbetween 7,000 and10,000 R'. P. ML, this depending upon the amount of separation desired,it follows that in case of accident to the motor or bowl, the springwould prevent its transmission from one to the other. Extending upwardlyinto the bowl to near the top and at the center thereof is an inlet tubel4 forfeeding the oil from the motor into the bowl. Thus, the inlet tothe bowl is at the bottom instead of at the top as is the usualpractice.

Surrounding this tube is a series of cylindrically formed portedchambers l5, l6 and I! through which the oil passes from one to theother until it is finally discharged also at the bottom of the bowl backinto the motor.

The inlet tube I4 is located within a larger tube 7 l4 forming the innerwall of the chamber i! and has at the top thereof and just above theupper or outlet end of the tube 14, an impeller or propeller l8 of screwor worm form, the rotation of which with the bowl assists in forcing theliquid from the tube l4 through the laterally extending ports a formedin a top cover disk 19 of the bowl into the top of the outer annularchamber I5 from which it passes at the bottom of this chamber I5 throughthe ports 1) into the bottom of an intermediate annular chamber 16 fromwhich it passes at the top thereof through ports e into an inner annularchamber I1 from which it passes through ports f at the bottom thereofthrough the outlet ports 9 of the base housing of the centrifuge back tothe motor.

It will thus be observed that as the oil passes from the motor into thetube M at the bottom of the centrifuge, it is circulated through-theentire lengths of the various chambers, as indicated by the arrows onthe drawings, and during this circulation and rotation, it is cleaned ofall foreign particles which are thus removed therefrom before thepassage of the oil back to the motor.

Thus, the dirty oil entering the centrifuge from the motor is cleanedand clarified and so passes back into the motor practically in the samecondition as when it was first poured thereinto and, consequently, thebearings and other moving parts of the motor are not injured by theforeign matter which is picked up by the oil during its circulationthrough the motor as would be the case where this oil continued tocirculate through the motor or even with filters which imperfectly cleanit.

At the top of the tube l4 there is clearance between this tube l4 andthe screw [8. This is to provide an overflow in case flow of oil becomesblocked in its passage at some place in the bowl. If this happens, theoil will then pass down the chamber or tube [4' formed between the tubel4 and this tube M past a clearance ring [4" at the bottom of the tubeI4 into a chamber 24 and out the vent 25.

Also, as the all returns to the centrifuge from the motor, it has fromfifty to seventy per cent air. This air must be removed. As the oil onlyis forced through the screw IS, the air entering the centrifuge with theoil is forced down the overflow chamber or tube 14' past the ring l4"intothe chamber 24 and out the vent 25, thus eliminating de-airing tanksnow used with motors.

It will be observed that the several chambers and the bowl parts arereadily assembled and separablejorcleaning purposes and for the removalof the sludge that may accumulate in the bottom of any chamber.

The oil circulating in motors of the class described is usually pumpedinto the pipe lines under a considerable pressure, for instance, fromtwenty-five to forty pounds. Consequently, since the oil pressure isnaturally reduced when the oil passes from the motor into the centrifugefor cleaning as it passes through the centrifuge at gravity feed, whenthe oil passes back from the centrifuge to the motor, it is essentialthat it pass into the motor under pressure and, for this purpose, thisimproved centrifuge is provided with means for passing the oil from thecentrifuge into the motor under the desired pressure and since theavailable space, as before stated, is very limited, especially inaeroplanes and tanks, this pressure means, in the form of a pump, is apart of the centrifuge and is located at the bottom of the bowl and inthe housing supporting that bowl, the housing being constructed for thatpurpose.

In one form thereof (see Fig. 4) the bowl spindle 8 is extended as bymeans of a shaft or supplemental spindle 8 suitably connected to orintegral with the spindle 8 and which, likewise, is carried by ballbearings 20 and 2|.

The inlet tube 14 is likewise extended to pass therethrough and thisshaft is provided with vanes or spiral leaves 22 which act as a pump sothat during the rotation of the bowl and its shaft, when the oil flowsfrom the various chambers through the outlet of the bowl bottom into thehousing 2 and before its passage therefrom, it is picked up by the vanesand forced through the outlet g of the housing at substantially the samepressure as when it was originally passed into the bowl and, therefore,a perfect cycle of the oil and clarification thereof is obtained with noloss of pressure since the'oil is forced back into the motor undersubstantially the same pressure as when it left the motor.

The vanes of this pump are formed like the threads of a screw and thepitch may vary to determine the amount of pressure.

In the form shown in Figs. 2 and 3 which is adapted especially foraeroplane motors where sufficient space is not available to take care ofthe extended shaft 8' of Fig. 4, the unit is provided with vanes 23directly underneath the bottom of the bowl and rotate therewith.

These vanes may be formed as a part of the bottom disk of the bowl andpick the oil up immediately on its passage from the outlet f of the bowland thus build up the pressure before it passes from the bowl and itshousing back to the motor.

Thus, by this very simple, compact and efficient centrifuge, the oil ofthe motor may be readily cleansed of its various foreign particles as itcirculates from the motor to and through the centrifuge and not onlythis, but is fed back to the motor under substantially the same pressureat which it is maintained during its passage in the motor.

It is to be understood that, by describing in detail herein anyparticular forms, structure or arrangement, it is not intended to limitthe invention beyond the terms of the several claims or the requirementsof the prior art. 7

Having thus explained the nature of my said invention and described away of constructing and using the same, although without attempting toset forth all of the forms in which it may be made or all of the modesof its use, I claim:

1. A centrifuge comprising a housing-supported casing, a bowl supportedin said casing for rotation and having ball-supported tapered spindles,a motor supported by the casing at the top of the bowl for rotating saidbowl, said bowl comprising a plurality of cylinder-formed chamberstherein,

arrears? said; chambers-J having communicatmg: ports so located as topass: the fiuidlfrom; the center of" the bowl: to the: outer chamber andfrom thencetoward the centerof rotation through. adjacent chambers andthroughout: the length. of all. the chambers,. the. bowl havingcentrally thereof. an inlet at itsbottom. andalso. an. outlet at. itsbottom communicating. with. the innermost. chamber.

2; A. centrifuge comprising a housing-supported. casing, a bowlsupported in: said. casing for rota.- tion, a. motorsupported. abovesaid. bowl forr'o'tating it, said. bowl comprising a. plurality oicylinder -formed. chambers therein; said chambers hav' ing communicatingportsv so: located: as to pass. the. liquid. from the; center: of. thebowl to. the outer chamber. and. from thence toward; the. center' of.rotationthroughadjacent chambers andthrough out the length of all thechambers, the. bowlhaving centrally thereof. an inlet at its bottom andalso an outlet at its. bottom communicating. with the innermostchamber,- said. inlet extending to near. the; top of the bowl, and animpeller located: at the top of said inlet.

3, A. centrifuge comprising. a: housing-.-supp'orted casing, a. bowlsupported in said casing forrotation and having ball-supported. taperedspindles, a motor supportedby the casing; at the top of the bowl forrotating said. bowl, said bowl: comprising a plurality ofcylinder-formed. chambers therein, said chambers having communicatingports so located as to passthe fluid from. the center-f the bowl to theouter chamber. and. from. thence; toward the center of. rotation.through: adjacent chambers and. throughout. the length of all thechambers, the bowl having; centrally thereof an inlet. at its bottom andalso an outlet atits bottom communicating with. the. innermost.chamber,, said inlet extending to-near' the top of. the: bowl, and animpeller located at the top of said. inlet;

4. A centrifuge comprising.ahousing-supported casing, a bowlsupported insaid casingv for rotation, a motor supported above said. bowl. forrotating; it, said bowl comprising a. plurality of cylin der-formedchambers therein, said chambers hav ing; communicating port's. so.located. as to pass the fluid fromthecenter ofz'thebowl to the-outerchamber and. from. thence. toward. the center" of rotation throughadjacent: chambers. and throughout the length. oi all the chambers; thebowl havingv centrally" thereof. an inlet at. its: bottom and. also anoutlet at its bottom communieating with the innermost. chamber; saidinletv comprising. a tube located within a larger tube: forming theinner wall of therinner. chamber. of the bowl and having its outletbelow the top of the bowland incommunicati'onwith.laterally ex tending.ports in atop cover'disk of. the bowl, and an impeller located between.said: tube outlet: and saidlast'portsz.

5:. A centrifugecomprising a housing' supported casing, a rotatablebowl, spindle supported at-the top and bottomin suchcasing, a motorhaving a tapered cushioned slip joint connection with the bowl andsupported by the casi'ngat the topof the bowl for rotating said bowl,said bowl having a plurality of cylinder-formed. nested. chamberstherein, said" chambers. having communicating ports alternately locatedat the top and bottom of the chambers so as tov pass the fluidlengthwise through the chambers from the center of rotation to the outerchamber and from thence-back toward the center of rotation through anadjacent chambenthe inlet to and outlet from the bowl be.-- ing at thebottom thereof, andan. impeller.

cated at the toprof the bowl; and incommunica tion with. the inlet andouter chamber.

6.. A centrifuge. comprising. a. housin'g-F'supported casing, arotatable bowl, spindle supperteidiatthe topand bottom. in: such.casing, a motor having a tapered cushionedslipjoint connection withthebowl: and supported by a. casing'at the. top. of the bowl for rotatingvsaid bowl, said; bowl having a plurality of cylind-er formed nested:chambers therein, saidi chambers having communicating ports alternatelylocated. at the top. and. bottom ofthe: chambers'soas to pass the fluid:lengthwise through the chambers'f'romthe center-of rotation to theouter: chamber" and. from. thence back: to?- ward the center of rotationthrough an adjacent chamber, the: inlet to: and. outlet from the bowlbeing at the bottom thereof, an impeller: located at the top of the bowland in. communicationwith the inlet and outer chambenand. rotatablemeans for. increasing. the pressure of the fluid. assing. from the bowland located below the bottom of the bowl and in communication with theoutlet therefrom and. rotable' with the bowl.

7. Acentrifuge comprising a housing-supported: casing, a rotatable bowl,spindle: supported. at its top and bottom. in such casing, a motorhaving a tapered cushioned slip joint connection. with the bowl. and.supported by the. casing at. the top of. the bowl for rotating said:bowl, said bowl having; a. plurality of. cylinder -formed nestedchambers therein, said. chambers having com-- municating. portsalternately located at the: top? and bottom. of. the chambers so as. to.pass. the fluid lengthwise through the chambers. from the center ofrotation to the outer chamber. andf-rom thence back toward the center ofrotation through an adjacent chamber, theinlet to and outlet from thebowlbeing at the'b'ottom'thereof,

the lower: spindle of. the bowl having an supple-.

mental ball-supportedspindle, said housing having an outlet, anclimeans. carried by said supplemental spindle for: increasing the.pressure.- 01'; the fluid. as it leaves the-bowl and passes through thehousing outlet of the centrifuge.

8. A centrifuge-comprising.ahousing-supported;

casing, a bowl supported in said. casing forv ro tation, a motorsupported. above. said: bowl for rotating it,, said bowl. comprising aplurality of. cylinder-formed. ported. chambers therein. and. having. anoutlet-at its. bottom. and an inlet. contrally thereof also at its.bottom and. communieating with the: top of the-bowl, and: an impeller atthe top of the bowl communicating with said inlet and. with a chamber ofthe bowl.

9. Acentrifuge comprising ahousing-supported casing, a. bowlsupported insaidcasing for rota:- tion, a motor supported. above said bowl. for.rotating it, said bowl: comprising. a plurality oi cylinder-formedported chambers. therein and having an outlet 'atits bottom. and aninlet centrally thereof also at its bottom and communicating with thetop of the bowl, an impeller at the top of the bowl communicating'withsaid'inlot and with a chamber of the bowl, and means located belowthebottom of the bowl and re tatable therewith for increasing thepressure of r the fluid passing fromthe-bowl.

bearing supported spindles; a motor supported.

above said bowl'for. rotating it, said.bowl.compris-- ing a plurality ofcylinder forme'd ported chamaberstherein. and having. an. outlet at; itsbottom: and. an inlet. centrally thereofalso at its. bottom andcommunicating with the top of the bowl, and an impeller at the top ofthe bowl communicating with said inlet and with a chamber of the bowl.

11. A centrifuge comprising a housing-supported casing, a, bowlsupported in said casing for rotation and having a pair of taper-formedball-bearing supported spindles, a motor supported above said bowl forrotating it and a tapered spring-cushioned connection between the motorand the upper tapered spindle of the bowl, said bowl comprising aplurality of cylinderformed ported members therein and having an outletat its bottom and an inlet centrally thereof also at its bottom andcommunicating with the top of the bowl, and an impeller at the top ofthe bowl communicating with said inlet and with a chamber of the bowl.

12. A centrifuge comprising a housing-supported casing, a bowl supportedin said casing for rotation and having ball-supported tapered spindles,a motor supported by the casing at the top of the bowl for rotating saidbowl, the upper tapered bowl spindle having a tapered seat and a taperedand spring-cushioned bushing connecting the shaft of the motor and bowl,said bowl comprising a plurality of cylinder-formed chambers therein,said chambers having communicating ports so located as to pass the fluidfrom the center of the bowl to the outer chamber and from thence towardthe center of rotation through adjacent chambers and throughout thelengths of all the chambers, the bowl having centrally thereof an inletat its bottom and also an outlet at its bottom communicating with theinnermost chamber, the top of the bowl having laterally extending portscommunicating With the inlet and with the outer chamber, a screw-formedimpeller at the top of the inlet adjacent to the top of the bowl and incommunication with the laterally extending ports leading to the outerchamber, and vane-formed means located below the bottom of the bowl androtatable therewith and communicating with a housing outlet below thebottom of the bowl for increasing the pressure of the fluid passing fromthe bowl.

13. A centrifuge comprising a housing-supported casing, a bowl supportedin said casing for rotation, a motor supported above said bowl forrotating it, said bowl comprising a plurality of cylinder-formed portedchambers therein and having an outlet at its bottom and an inletcentrally thereof also at its bottom and communicating with the top ofthe bowl, and an impeller at the top of the bowl communicating with saidinlet and with a chamber of the bowl and outlet means below the impellerand around said central inlet for de-airing the fluid.

14. A centrifuge comprising a housing-supported casing, a bowl supportedin said casing for rotation, a motor supported above said bowl forrotating it, said bowl comprising a plurality of cylinder-formed portedchambers therein and 7 vented chamber below said overflow chamber forthe reception of said overflow fluid.

15. A centrifuge comprising a housing-supported casing, a bowl supportedin said'casing for rotation, a motor supported above said bowl forrotating it, said bowl comprising a plurality of cylinder-formedchambers therein, said chambers having communicating ports so located asto pass the liquid from the center of the bowl to the outer chamber andfrom thence toward the center of rotation through adjacent chambers andthroughout the length of all the chambers, the bowl having centrallythereof an inlet at its bottom and also an outlet at its bottomcommunicating with the innermost chamber, said inlet extending to nearthe top of the bowl, and an impeller located at the top of said inletand outlet means below the impeller and around said central inlet forde-airing the fluid.

16. A centrifuge comprising a housing-supported casing, a bowl supportedin said casing for rotation, a motor supported above said bowl forrotating-it, said bowl comprising a, plurality of cylinder-formedchambers therein, said chambers having communicating ports so located asto pass the fluid from the center of the bowl to the outer chamber andfrom thence toward the center of rotation through adjacent chambers andthroughout the length of all the chambers, the bowl having centrallythereof an inlet at its bottom and extending to communicate with the topof the bowland also an outlet at its bottom communicating with theinnermost chamber, said housing having an outlet below the bottom of thebowl, means located below the bottom of the bowl and in communicationwith the housing outlet for increasing the pressure of the fluid passingfrom the bowl, an impeller located at the top of said inlet, and meansbelow the impeller and adjacent to said central inlet for de-airing thefluid and comprising an overflow chamber around the centrally locatedinlet and having a clearance or port at its bottom for the passage ofoverflow fluid and the removal of air from the 5 l=fluid and a ventedchamber below said overflow chamber for the reception of said overflowfluid.

17. A centrifuge comprising a housing-supported casing, a bowl supportedin said casing for rotation, a motor supported above said bowl for'rotating it, said bowl comprising a plurality of the top of the bowlcommunicating with said inlet and with a chamber of the bowl, meanslocated below the bottom of the bowl and rotatable therewith forincreasing the pressure of the fluid passing from the bowl, and outletmeans below the impeller and around said central inlet for de-airing thefluid.

18. A centrifuge comprising a supporting base, a casing secured thereto,a cover for the casing, a rotary bowl in said casingand having taperedspindles at its top and bottom, ball bearings at the bottom of the bowlbetween one of said tapered spindles and base, ball bearings between thecover and the other of said tapered spindles, a motor on the cover andhaving spring-cushioned driving means to the top tapered spindle of thebowl, said bowl having an inlet and an outlet, .both at the bottom ofthe bowl, the inlet located centrally of the bowl and in communica: tionwith ported chambers within the bowl for separating the fluid.

.9 19. A centrifuge comprising a supporting base, a casing securedthereto, a cover for the casing, a rotary bowl in said casing and havingtapered spindles at its top and bottom, ball bearings at the bottom ofthe bowl between one of said tapered spindles and base, ball bearingsbetween the cover and the other of said tapered spindles, a motor on thecover and having wring-cushioned driving means to the top taperedspindle of the bowl, said bowl having an inlet and an outlet, both atthe bottom of the bowl, the inlet located centrally of the bowl and incommunication with ported chambers within the bowl for separating thefluid, and an impeller located at the top of the bowl and incommunication with the inlet located centrally of the bowl.

2 0. A centrifuge comprising a supporting base, a casing securedthereto, a cover for the casing, a rotary bowl in said casing and havingtapered spindles at its top and bottom, ball bearings at the bottom ofthe bowl .between one of said tapered spindles and base, ball bearingsbetween the cover and the other of said tapered spindles, a motor on thecover and having driving means to the top tapered spindle of the bowl,said motor having a diameter substantially no greater than the diameterof the supporting casing, said bowl having an inlet and outlet both atthe bottom of the bowl, the inlet located centrally REFERENCES CITED Thefollowing references are of record in the file of this patent:

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